Better support of IPv6 scoped addresses.
- most of the kernel code will not care about the actual encoding of
scope zone IDs and won't touch "s6_addr16[1]" directly.
- similarly, most of the kernel code will not care about link-local
scoped addresses as a special case.
- scope boundary check will be stricter. For example, the current
*BSD code allows a packet with src=::1 and dst=(some global IPv6
address) to be sent outside of the node, if the application do:
s = socket(AF_INET6);
bind(s, "::1");
sendto(s, some_global_IPv6_addr);
This is clearly wrong, since ::1 is only meaningful within a single
node, but the current implementation of the *BSD kernel cannot
reject this attempt.
- and, while there, don't try to remove the ff02::/32 interface route
entry in in6_ifdetach() as it's already gone.
This also includes some level of support for the standard source
address selection algorithm defined in RFC3484, which will be
completed on in the future.
From the KAME project via JINMEI Tatuya.
Approved by core@.